Polymyositis and Dermatomyositis

Question 1

What is polymyositis and dermatomyositis?

Answer 1

An autoimmune disorder of chronic inflammation, of muscles and skin

Polymyositis primarily affects muscle tissue, while dermatomyositis includes skin manifestations.

Question 2

What do blood tests show in polymyositis and dermatomyositis?

Answer 2

Elevated Creatinine Kinase

This enzyme is released when muscle tissue is damaged.

Question 3

What auto-antibodies are associated with polymyositis and dermatomyositis?

Answer 3

Anti-Jo, Anti-Mi2, ANA

These antibodies can help in diagnosis and indicate the presence of autoimmune activity.

Question 4

What are the clinical features of polymyositis?

Answer 4

Muscle pain, fatigue, weakness, bilaterally affecting shoulder muscles and pelvic girdle, lasts many weeks

Symptoms often develop gradually over several weeks.

Question 5

What are the clinical features of dermatomyositis?

Answer 5

Proximal muscle weakness
Gottron papules, purple heliotrope rash on eyelids and face, photosensitive rash on back, subcutaneous calcinosis, Raynaud’s, periorbital oedema

Skin manifestations are key differentiators from polymyositis.

Question 6

What should also be investigated in cases of polymyositis and dermatomyositis?

Answer 6

It is also a paraneoplastic syndrome, hence investigate for malignancy i.e. Breast, Lung, Ovarian, Gastric

Early detection of associated malignancies can significantly affect management and prognosis.

Question 7

What is the management for polymyositis and dermatomyositis?

Answer 7

Corticosteroids

These are typically the first line of treatment to reduce inflammation.